In the static measurement, the plate remains in contact with liquid during the entire cycle of interfacial tension measurement. If the instrument operates in the detachment mode, the interfacial tension is measured by measuring the force required to separate the ring or plate from contact with the interface. instruments use plates of standard dimensions so that measurements of the plate size and its weight are not required. Adsorption of organic compounds from the laboratory environment or test solutions can be a major source of experimental error when measuring surface tensions using the Wilhelmy plate method. Du Nouy ring method